
function GetXmlHttpObject()
{
var xmlHttp=null;
try
 {
 // Firefox, Opera 8.0+, Safari
 xmlHttp=new XMLHttpRequest();
 }
catch (e)
 {
 // Internet Explorer
 try
  {
  xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
  }
 catch (e)
  {
  xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
 }
return xmlHttp;
}

function GetCityName()
{
 var xmlHttp = GetXmlHttpObject();
 xmlHttp.onreadystatechange=function()
      {
		if(xmlHttp.readyState==4)
		{
			if(xmlHttp.status==200)
			{			    
				var str = xmlHttp.responseText;
                alert(str);
			}            
       }	  
	  }	 
	 var localIP=""; 
	 //"http://ip.qq.com/cgi-bin/searchip?searchip1="+localIP
	xmlHttp.open("GET","GetLocation.php",true);
    xmlHttp.send(null);	
}